Cholesterol: Properties, Processing Effects, and Determination

Cholesterol is a small, yet complex four-ring molecule providing vital biological functions for the eukaryotic cell membrane. Although cholesterol is the sole precursor of many steroid hormones required for the growth, development, and reproduction of mammals, the lethal effects of excess serum cholesterol have been well documented. Primary sources of cholesterol in foods are meat, poultry, eggs, dairy, and seafood. Food processing primarily causes changes in cholesterol content through moisture loss and oxidation. Cholesterol oxidation products, although occurring in minute amounts compared with cholesterol, may potentially pose greater risks to human health because of their toxicity. The determination of cholesterol is simpler than that of cholesterol oxides because cholesterol exists in a much greater concentration and less susceptible to further degradation during analytic procedures. Cholesterol and cholesterol oxides are primarily determined by gas chromatography and high-pressure liquid chromatography coupled with detection means from as simple as flame ionization or ultraviolet absorption to as complicated as electrochemistry or mass spectrometry.